Process for preparing colored polyurethane

ABSTRACT

A colored polyurethane material is prepared by reacting a polyisocyanate compound and a polyhydroxyl compound with a complex metal dye which contains at least one amino group or a hydroxyl group with one active hydrogen atom whereby the polyurethane material is colored by the presence of the chemically bonded complex metal dye.

United States Patent 1191 Maeda et a1.

[451 Apr. 29, 1975 PROCESS FOR PREPARING COLORED POLYURETHANE [75]Inventors: Shigeo Maeda; Minoru Ozutsumi; v

Isao Niimura; Hideo Okazaki, all of Tokyo, Japan [73] Assignee: HodogayaChemical Co., Ltdl,

Tokyo, Japan [22] Filed: Aug. 10, 1973 [21] Appl. No.: 387,504

[52] U.S. Cl 260/37 N; 260/75 NH; 260/75 NP; 260/77.5 AM; 260/145 A;260/147; 260/149;

[51] Int. Cl C08g 51/66 [58] Field of Search 260/37 N, 37 NP, 77.5 AQ,260/77.5 AP, 77.5 AM, 75 NH, 75 NP, 75

[56] References Cited UNITED STATES PATENTS 3,062,831 11/1962 Freyermuth260/3l4.5

3.261.827 7/1966 Boresch 260/314.5 3,278,486 10/1966 Meek 260/77.5 AP3,625,937 12/1971 Scholl.... 260/37 N 3.730.950 5/1973 Barnes 260/37 NPrimary Examiner.loseph L. Schofer Assistant Examiner-Paul R. MichlAttorney, Agent, or Firm-Oblon, Fisher, Spivak, McClelland & Maier [57]ABSTRACT 6 Claims, No Drawings PROCESS FOR PREPARING COLOREDPOLYURETHANE BACKGROUND OF THE INVENTION 1. Field of the Invention Thisinvention relates to a process for preparing colored polyurethanematerial.

2. Description of the Prior Art In the past colored polyurethanematerials have been prepared principally by coloring polyurethanes witha pigment, dye or a coloring agent consisting essentially of a pigmentor dye. However, when polyurethane materials are colored witha'pigment', the resulting product is only lightly tinted or it may havea dark hue. On the other hand, if a dye is used to color'the product,the water-resistance, oil-resistance, resistance tobleeding,light-fastness, or the. like of the product is often disadvantageously,inadequate: When adye is used as the coloring agent, it ishard 'to preventbleeding of the dye from the colored polyurethaneproduct-However, col-- ored polyurethane products, when colored with adye, have the advantage of possessing a clear'hue'and transparency. Ofcourse, polyurethane materials of many different'colors can be produced,limited only by the types of dyes available. For these reasons dyes havechiefly been used to color polyurethane materials, even. though dyeshave the previously described disadvantagcs.

A need, therefore, exists for a coloring agent which has excellent colorfastness, water resistance, oil resistance, bleeding resistance andlight fastness.

SUMMARY OF THE INVENTION Accordingly, one object of this invention is toproas hereinafter will become more readily apparent-can;

be attained by a process for preparing a colored polyurethane materialwhich comprises reacting a polyisocyanate compound and a polyhydroxylcompound with a complex metal dye which contains at least one aminogroup or a hydroxyl group having oneactive hydrogen atom, whereby thepolyurethane material is colored by the presence of the chemicallybonded complex metal dye.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the process of the inventionthe coloring agent of the invention colors polyurethane materials by amechanism which is different from the mechanism by which polyurethanematerials are colored with conventional pigments or dyes. Theconventionally colored polyurethane materials contain a pigment or a dyewhich is simply dispersed or solubilized by a mechanical process in thepolyurethane. On the other hand, polyurethane materials are colored withthe coloring agent of the invention by a mechanism in which a complexmetal dye, which has an active hydrogen atom, is reacted with anisocyanate group of a polyisocyanate substrate which is one of thecomponents of-a polyurethane. By this mechanism, the complex metal dyeis chemically bonded to the polyurethane molecule. As a result, thebleeding resistance and the light fastness of the colored polyurethaneproduct is substantially improved.

The complex metal dye which has at least one amino group or hydroxylgroup with an active hydrogen atom, reacts with the isocyanato group ofthe polyisocyanate substrate, which substrate also reacts with a polyolor the polyurethane base to form a coiored polyurethane product containing a bonded complex metaldye. The polyisocyanate 'substra'te hasat least two isocyanate groups an'd 'reacts with a polyol or' apolyurethane to form a higher polyurethane product. Suitablepolyisocyanate substrates are disclosed in J. H. Saunders and K. C.Frisch, Po'lyurethan es: Chemistry and Technol-. ogy I Chemistry, Partl, pages '9 12, pages 347 348 1962). I

In the process of the invention it is especially preferable to use aprepolymer which has at least two terminal isocyanate groups such astriisocyanates which are prepared by reacting 1 mole oftrimethylol-propane with 3 moles of 2,4-tolylene diisocyanate orhexamethylene 'diisocyanate, or diisocyanates which are prepared byreacting propyleneglycol adipate with a diisocyanate. Suitablepolyhydroxyl compounds which are reacted with the polyisocyanate groupsinclude polyester polyols, polyether polyols or polyurethanes which haveactive hydrogen atoms which react with the isocyanate groups of thepolyisocyanate. Suitable polyols and polyurethanes which react with thepolyisocyanate compounds are disclosedin the previously mentioned book,l-"' olyurethanes,-- pages 32 47-and pages 349 35l. Poly'ols having anOH value of IO 50 are especially;preferred, and can be prepared byreacting a coester-of ethyleneglycol and diethyleneglycol adipate withtolylene diisocyanate. Other preferred polyols includepolytetramethyleneglycolwhich has an OH value of or polypropylene glycolwhich has an OH value of 80 160.

The complex metal dye which has at least one amino l group or hydroxylgroup with an active hydrogen atom include 2 1 complex metal dyes, l 1complex metal dyes, Cu-phthalocyanine dyes, complex metal formazan dyes,and the like. All of these metal dyes contain an alkylamino group, anamino group containing a nondissociated substituent or an alcoholichydroxyl group. Suitable 2 1 complex metal dyes include those which havean amino group ora hydroxyl group with an active hydrogen atom and whichhave the following formulas (Y) D n wherein A and A can be the same ordifferent and each can represent a residual phenylene radical which canhave a non-dissociated substituent; B and B can be the same or differentand each represents a residual coupling component which can have anon-dissociated substituent and which have the metal coupling D and D'groups disposed in an ortho relationship to the bridging azo groups; Zand Z can be the same or different and each represents an -O. or COO-group which is disposed in an ortho relationship to the bridging azogroups through groups A and A; D and D can be the same' or different andeach represents -O-. -NH-. or

wherein R and R represent hydrogen, lower alkyl, amino or hydroxysubstituted lower alkyl. N-alkylamino orN-hydroxylalkylamino-substituted lower alkyl groups wherein at least oneof the R, and R groups is an active hydrogen atom: and R. and R can becycylized together to form a hetero six membered ring with the nitrogencontaining imino group; X;, represents --SO -NHSO CO, or NHCO; and arepresents an integer from 1 to 4; and Y can bond with A or B or both Aand B.

The 2 l complex metal dyes can be prepared by reacting a chromium orcobalt metallizing agent by any 5 conventional process with a monoazodye having the i formula LA N N -\B b (2) q o. X X

A N N b (2') (so H) M represents a chromium or cobalt atom; [K]represents hydrogen ion. sodium ion. ammonium. aliphatic and substitutedaliphatic ammonium or acyclic ammonium; K represents aliphatic andsubstituted aliphatic ammonium or acyclic ammonium and n represents anwherein A and B are defined as above; X represents a hydroxyl orcarboxyl group; X represents hydroxyl. amino or lower alkylamino; b is lor 2; and c is l 2 or 3.

integer from 1 to 6. ln formulas l) and (1') Y repre- 45' Suitablecopper phthalocyanine dyes include those sents which have the formula-(CH)-0H (4 R -X-(CH)-N R (5) -X -(CI-I)-OH (6) I -X-N(CH)-N (7) V 2 F10! lololnclliollcioboolo wherein CuPc represents a chlorinated ornonchlorinated copper phthalocyanine moiety; R represents hydrogen,alkyl, or hydroxyalkyl; R represents wherein E represents a substitutedalkylene group containing at least one X group wherein X, representshydroxyl, amino, alkylamino or an alkylamino group substituted with anondissociable group; F represents a substituted alkylene groupcontaining at least one X group wherein X represents hydroxyl; Grepresents SO or CO-; X,; represents hydrogen, alkyl or hydroxyalkyl andX; represents amino, alkylamino or hydroxyl substituted alkyl amino; Rrepresents hydrogen or alkyl; R represents alkyl oran alkyl groupsubstituted with a nondissociable group; represents an integer from l to4; represents 0 or an integer from lto3andx+yisl,2,3or4.

The 2 1 complex metal dyes as well as the copper phthalocyanine dyes aredisclosed in the copending applications Ser. Nos. 376,365 and 376,387.

In the preparation of the colored polyurethane materials the complexmetal dye which containsan amino group or a hydroxyl group is usuallyfirst dissolved in an inert solvent such as dimethylformamide,methylethylketone, toluene, ethylacetate, acetone, tetrahydrofuran, orthe like. However, a solvent mixture of tetrahydrofuran anddimethylformamide is especially preferred. The complex metal dye canthen be reacted with a prepolymer prepared by reacting an excessquantity ofa polyisocyanate' with a hydroxyl compound such as a polyol,For example, one typical prepolymer is prepared by reacting2,4-tolylenediisocyanate with a polyester polyol which in turn isprepared by reacting adipic acid with propyleneglycol. The coloredpolyurethane materials can be prepared in a solution, as an emulsion. asan aqueous dispersion, as an elastomer. or the like depending upon theselection of the starting materials which include the solvent, thepolyisocyanate, the polyol, and the polyurethane.

Ioooloollolllnlcollll The following descriptions are brief discussionsof various forms of colored polyurethane materials.

I. Preparation of a colored polyurethane solution (dope) l. A complexmetal dye which contains an active hypolyhydroxyl compound in an inertsolvent which does not react with the isocyanate group.

2. A prepolymer which contains an isocyanate group is prepared byreacting a polyhydroxyl compound with a polyisocyanate compound, andthen the prepolymer is chain-extended with a complex metal dye whichcontains an active hydrogen atom in an inert solvent.

3. A prepolymer is prepared by reacting a polyisocyanate in an inertsolvent with a complex metal dye which contains an active hydrogen atomand a polyol, and then the colored prepolymer is chain-extended byreacting it with a compound which contains two active hydrogen atomssuch as hydrazine, hydroxylamine, polyoxyethylene polyol, polyesterpolyol, water, or the like.

ll; Preparation of a colored dispersion l. A prepolymer is prepared byreacting a polyisocyanate with a complex metal dye which contains anactive polyurethane aqueous hydrogen atom and a polyhydroxyl compound,which at the same time reacts with a compound which contains an activehydrogen atom and a compound containing a salt forming group. Theresulting polyurethane-product is converted to the salt form, ifnecessary. and then is dispersed in water.

2. A prepolymer is prepared by reacting a polyisocyanate with a complexmetal dye which contains an active hydrogen atom and a polyhydroxylcompound in an inert solvent. The polyurethane solution is then admixedwith a surfactant, preferably a nonionic surfactant, and water and thenhomogenized to form an aqueous dispersion of the polyurethane.

action solution during the polymerization reaction while unreactedisocyanate groups remain. The following reaction sequences show some ofthe different means by which colored polyurethane products can beprepared. l. Complex metal dye is bonded to a polyurethane substrate byurea bonds 1. A complex metal dye with one active hydrogen atom complexmetal dye -]NH OcNf wvvw ww-} NCO HOW OH [complex metal dye}--NHCONHWNHEO OCONHM- --N'HCON'H [comp1ex metal dye 2. A complex metal dyewith two active hydrogen atoms H0 OH 3. A complex metal dye with threeactive hydrogen atoms 9 10 II. A complex metal dye is bonded to apolyurethane l. A complex metal dyewith one active hydrogen substrate byurethane bonds atom eozin nlexlmetal dye-A 2 or; ma 4; NCO

.[ complex metal dye-+1 1.. iv. a 0 i, O; O Y

complex metal dye 2. A complex metal dye with two active hydrogen atoms3. A complex metal dye wigh three active hydrogen atoms cNH-+ o iimw u x1 1 In the formulas of the equations, K represents hydrogen ion, alkalimetal ions. ammonium ions, aliphatic ammonium ions. or acyclic ammoniumions; and x represents an integer.

The colored polyurethane products of this invention have manyapplications, because of their chemical and physical properties. Forexample. the colored polyurethane products can be used in coating agentsfor various substrates, paints. inks, lacquers, bonding agents. waterrepelling agents, wire coatings and in the soles of shoes.

Having generally described this invention. a further understanding canbe obtained by reference to certain specific examples which are providedherein for purposes of illustration only and are not intended to belimiting unless otherwise specified.

dissolved in 40 parts of tetrahydrofuran. A solution of 60 2.3 parts of4.4. -diphenylmethane diisocyanate in 10 parts of tetrahydrofuran andparts of a polyol which is prepared by reacting tolylene diisocyanatewith the adipic acid coester of ethyleneglycol and diethyleneglycol (OHvalue was added to the dye solution and the mixture was stirred-at C for4 hours. A colored polyurethane dope was thereby obtained.

When polytetramethyleneglycol (OH value 86.3) or polypropyleneglycol (OHvalue [12.2) was used instead of the polyol prepared above. a similarcolored polyurethane dope was obtained. Further, when urethanetriisocyanate prepared by reacting 3 moles of tolylenediisocyanate orhexamethylene diisocyanate with 1 mole of trimethylol propane was usedinstead of 4,4'-diphenylmethane diisocyanate, a similar coloredpolyurethane dope was obtained.

EXAMPLE 2 4.6 Parts of 4,4-diphenylmethanediisocyanate was added to 1 L6parts of polytetramethyleneglycol (OH value 95) at C with stirring. andthe mixture was reacted at 96 97C for 2 hours whereby a prepolymer wasprepared. 50 Parts of tetrahydrofuran was then added to dissolve theprepolymer.

63 na c n oc a 4.0 Parts of the 2 l complex chromiun dye with theformula above which contains amino groups were dissolved in 80 parts oftetrahydrofuran, and the solution was admixed with the stirredprepolymer solution prepared above at 62 63C whereby the components werereacted for 2 hours. By this procedure was obtained a black polyurethanedope.

When polypropylene glycol (OH value ll2.2) was used instead ofpolytetramethyleneglycol. a similar colored polyurethane dope wasobtained. Further. when urethane triisocyanate prepared by reacting 3moles of 2,4-tolylenediisocyanate or h xam th lenepolypropyleneglycol, asimilarly colored polyurethanediisocyanate with 1 mole of trimethylolpropane was i p n was Obtained- Further. when used instead of 44'-diphenylmethanediisocyanate. a nuphthylenediisocyanateo ,3-p y d s yna similar colored polyurethane dope was obtained. 2,4-tolylenediisocyanate or urethane triisocyanate pre- M LE 3 5 pared by reacting 3moles of 2,4-tolylene diisocyanate with one mole of trimethylol propanewas used instead of 4,4'-diphenylmethane diisocyanate, and N,N-dimethylethanolamine, N-methyl-N-(3-aminopropyl)- ethanolamine,N.N-dimethylethylenediamine or bis-( 3- CuPc aminopropyl)-methylaminewas used instead of N- 9 methyldiethanolamine. a similarly coloredpolyure- (sOaHNHCH CH CH N 9 )2 thane dispersion was also obtained.

(SO NHCH CH CH OH)- EXAMPLE4 Cll c N li c iiN o N a o Na s u /N Nac n No 0 5.2 Parts of the Cu-phthalocyanine dye with the for- 45 0-5 art O he2 I 1 complex Chromium ,dye with the h lamino groups was dismula abovewere added to 100 parts of vigorously formula f Ch h s H y I stirredpQIyprQpyIenegIy' I (OH v l 84) d th solved in a mut ture of 40 parts oftetrahydroffiurai} and 27.2 parts of 4,4'-'diphenylmethane diisocyanatewere Parts O (llmethylformamlde- 13 f 3 dP Wil added to the componentswhereby the reaction was ramethyleneglycol Value d ad 8 to t e conductedat C for 2 hours. 2.0 Parts of N- mixture, and 3.6 parts of 2,l-tolylenednsocyanate was methyldiethanolamine were added to the mixtureat 50 added f C with gOI S St rmg whereby a 55C whereby the componentswere reacted at 20 5 Y Q g Polyurethane 50 "P 1 300C for 4 hdurs and acolored rubbemike Polyqfiobtained. The solution was slowly added to avigorous y thane product was obtained. 88.8 Parts of a 24 percentstlfl'ed 9 of 2 Parts of p y y fl solution of the colored polyurethaneproduct in ace 55 ryletherm 100 parts of water, and then the mixture was.15 mole of trimethylol propane was usedjnstead of 2.4-tolylenediisocyanate, and a higher alcohol sulfate.alkyloxymethylpyridinum chloride or other surfactant was used instead ofpolyoxyethylene laurylether. a similarly colored polyurethane dispersionwas obtained.

1.5 Parts of an asymmetrical 2 1 complex chromium dye of the formulaabove was admixed with l'parts of stirred polytetramethyleneglycol (OHvalue 106) at 70 80C for 1 hour.

50.0 Parts of 4.4

- (SO2NRB 5CuPc (so H R R )y diphenylmethane diisocyanate was added tothe solution whereby the mixture was reacted for minutes. 22.2 Parts ofdihydroxyethyladipate was added to the stirred mixture for minutes. Theviolet colored viscous material obtained was poured into a cup which wascoated with a cured siliconmaterial, and was kept in the cup for about 3hours in a heater at C. A violet colored polyurethane elasto'mer whichhad no plasticity was obtained.

When the elastomer was cut into segments and weighed in a mold coatedwith a cured silicon material and the elastomer was compressed at Cunder 100 Kg/cm? for 15 minutes, the desired violet colored polyurethaneproduct was obtained. Further when polytetramethylene adipate (OH value156), polypropylene adipate (OH value 100) or polyethylene adipate (OHvalue 152) was used instead of polytetram'ethyleneglycol, a similarlycolored polyurethane elastomer was obtained. When 7 4,4'diphenyldiisocyanate; 1.5- naphthylenediisocyanate,hexamethylenediisocyanate or an isocyanate containing a prepolymerprepared' by reacting 2,4-tolylenediisocyanate with the polyester polyolof adipic acid and propyleneglycol, was used instead of4,4'-diphenylmethane diisocyanate, and when dihydroxyethyl succinate,'dihydroxybutyl adipate, o'r dihydroxyethyl isophthalate was usedinstead of dihydroxyethyl adipate, a similarly colored polyurethaneelastomer was obtained.

Having now fully described the invention, it will be apparent to one ofordinary skill in the artythat many changes and modifications can bemade thereto without departing from the spirit or scope of the inventionas set forth herein.

What is claimed as new and intended to be covered by Letters Patent is:

l. A process for preparing a colored polyurethane material, whichcomprises: i

s m a u reacting a polyisocyanate compound and a polyhydroxyl compoundwith av copper phthalocyanine dye of the formula I wherein R representshydrogen, alkyl or hydroxyalkyl; R represents E-X wherein E represents asubstituted alkylene group containing at least one X group 1 wherein Xrepresents hydroxyl, amino, alkylamino or an alkylamino groupsubstituted with a non-dissociable group; R represents hydrogen oralkyl; R represents alkyl or an alkyl group substituted with anondissociable group; x represents an integer from 1 to 4, y representsan integer from 1 to 3 and x y is 2, 3 or 4, which phthalocyanine dyecontains at least one amino group or a hydroxyl group having one activehydrogen atom.

2. The process of claim I, wherein said phthalocyanine dye, saidpolyisocyanate and said polyhydroxyl compound are polymerized in aninert solvent which is inert to the isocyanate groups present insolution.

4, The 'process of claim 1, wherein said phthalocyanine dye, saidpolyisocyanate and said polyhydroxyl compound are polymerized to form aprepolymer and then said prepolym'er is reacted with a. compound :hichcontains an active hydrogen atomand a salt 'l'he'process of'claim 1,wherein saidpolyisocyanate is a prepolymer which contains unreactedisocyanate groups.

at 6. Th e process of claim 1,'wherein said polyhydroxyl compound is apolyol or a polyurethane containing unreacted hydroxyl groups.

1. A PROCESS FOR PREPARING A COLORED POLYURETHANE MATERIAL, WHICHCOMPRISES: REACTING A POLYISOCYANATE COMPOUND AND A POLYHYDROXYLCOMPOUND WITH A COPPER PHTHALOCYANINE DYE OF THE FORMULA
 2. The processof claim 1, wherein said phthalocyanine dye, said polyisocyanate andsaid polyhydroxyl compound are polymerized in an inert solvent which isinert to the isocyanate groups present in solution.
 3. The process ofclaim 1, wherein said phthalocyanine is initially reacted with an excessamount of said polyisocyanate And then said polyhydroxyl compound isadded to said reacted polyisocyanate.
 4. The process of claim 1, whereinsaid phthalocyanine dye, said polyisocyanate and said polyhydroxylcompound are polymerized to form a prepolymer and then said prepolymeris reacted with a compound which contains an active hydrogen atom and asalt forming group.
 5. The process of claim 1, wherein saidpolyisocyanate is a prepolymer which contains unreacted isocyanategroups.
 6. The process of claim 1, wherein said polyhydroxyl compound isa polyol or a polyurethane containing unreacted hydroxyl groups.